Wireless communications systems are widely deployed to provide various communication services such as voice, video, packet data, messaging, broadcast, and the like. These wireless communications systems may be multiple-access networks capable of supporting multiple users by sharing the available network resources.
A wireless communications system may include a number of base stations or NodeBs that can support communication for a number of user equipments (UEs). A UE may communicate with a base station via downlink and uplink. The downlink (or forward link) refers to the communication link from the base station to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the base station.
The base station and the UE may each use multiple antennas when communicating with each other. In some cases, the UE may determine that the quality of its transmissions to the base station have deteriorated. The UE may determine this on its own, or after receiving feedback (or a lack of feedback—i.e., lack of acknowledgements) from the base station. Poor quality transmissions may result, for example, from a blocked antenna (e.g., as a result of a user having his or her thumb over an antenna) or over-the-air interference. To address this problem, the UE may initiate an antenna switch in which a transmit chain of the UE is switched to an alternate antenna. However, in some cases, the antenna switch for the transmit chain may necessitate an antenna switch for one or more of the UE's receive chains. Typically, an antenna switch for a receive chain will result in the loss of data. The data loss may be due, at least in part, to the settling time of the switching process.